I have been on this board every day for the last month since buying my car. I bought a nice clean 85 iroc, 305tpi, auto, 3.42 gears, t tops countour seats and only 50k on it.
This is my first chevy product in 25 years of driving. I have always owned and worked on international harvester v-8s.
The car runs and drives great, but I have a couple questions.
Do they all idle low? 500 rpm is were is is at now. I adjusted the iac and tps per this site. It used to die at idle before these adjustments. Also when adjusting the iac it states to jumper a and b, leave key on the unplug iac and start the car. Mine will not run with the iac unplugged.
Second question is do they all have to crank for a while before firing? Almost seems as though it is flooded. Once started it runs smooth.

Thanks for any help

 

Welcome to TGO. Great site. I believe spec is 750 at idle. Secondly, my TPI starts right up, but the RS TBI cranks a little before firing. It has always been that way for me. Have not messed w/ adjusting idle or iac and tps yet.

 

Idle for me is 500-600 . Cold starts "especially on the TBI" take a few cranks, but no more then 2-3 before it fires up once warm it fires up first crank, TPI's should be quicker 1-2 cranks on cold starts. If it seems to take a while before it fires up, could be time to replace that starter.

Isnt there a screw on the back of the throttle to adjust your idle? Im not sure about the TPI's

 

Not the starter. It spins over just fine, just takes some time to actually fire up.

 

I agree it is not the starter. Tps voltage at idle should be between .51-.53. Do you have any carbon build-up on the IAC? Did you read the FAQ article on IAC and TPS adjustment? That article states that the idle should be at 600 rpm in drive.

 

Well the iac was carboned up and seized. I put a new one in and have a nice 600 rpm idle now.

 

Update. After replacing the IAC, adjusting minimum air and setting TPS to spec I had a nice smooth 600 rpm idle. After an hour of driving over the weekend it is back to barely 500 just like before. Seems like the ecm overides any adjustment.
Also when decelerating for a stop the rms will drop to 1000 then briefly jump up to about 1700 and drop right back down.